Thanks for the advice. We did notice that our bottle was expired last year so we bought a new bottle, but we still had the same problem. Do you just use a plastic test tube to shake it in?shrewdPanther46 wrote:You probs have some old, old peroxide. Spontaneous decompositionknowthewrightstuff wrote:My team has had trouble identifying the difference between water and hydrogen peroxide since they are both odorless and have the same pH. We have tried shaking them and looking for bubbles, but both liquids bubble for us. Are there other methods we could try to effectively identify the difference between these liquids?
Crime Busters B
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Re: Crime Busters B
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Re: Crime Busters B
One way to tell them apart is to put some iodine in it. If it fizzes, it's hydrogen peroxide. If not, water.knowthewrightstuff wrote:My team has had trouble identifying the difference between water and hydrogen peroxide since they are both odorless and have the same pH. We have tried shaking them and looking for bubbles, but both liquids bubble for us. Are there other methods we could try to effectively identify the difference between these liquids?
"Blessed are you when people insult you and persecute you, and falsely say all kinds of evil against you because of Me. Rejoice and be glad, for your reward in heaven is great; for in the same way they persecuted the prophets who were before you." Matthew 5:11-12
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Re: Crime Busters B
The Society of Plastics Engineers sells a pretty comprehensive kit called Hands-On Plastics that has most everything except PMMA. A cheap way to get fibers is to go to the local craft/fabric store and see if they'll let you have 1-inch samples of fabrics for free or for really cheap.SOCoach wrote:Several years ago I bought a polymer / fiber kit for crimebusters that was really good. I can't seem to remember or find where I bought it from. Does anyone have a good site for getting fibers and plastics for crimebusters?
I'm not sure how you got that to happen bc if you try to write a balanced equation for it, you won't get a product that will be in gaseous form.Tailsfan101 wrote:One way to tell them apart is to put some iodine in it. If it fizzes, it's hydrogen peroxide. If not, water.knowthewrightstuff wrote:My team has had trouble identifying the difference between water and hydrogen peroxide since they are both odorless and have the same pH. We have tried shaking them and looking for bubbles, but both liquids bubble for us. Are there other methods we could try to effectively identify the difference between these liquids?
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Re: Crime Busters B
I found something on the H2O2/KI reaction here.pikachu4919 wrote:I'm not sure how you got that to happen bc if you try to write a balanced equation for it, you won't get a product that will be in gaseous form.Tailsfan101 wrote:One way to tell them apart is to put some iodine in it. If it fizzes, it's hydrogen peroxide. If not, water.knowthewrightstuff wrote:My team has had trouble identifying the difference between water and hydrogen peroxide since they are both odorless and have the same pH. We have tried shaking them and looking for bubbles, but both liquids bubble for us. Are there other methods we could try to effectively identify the difference between these liquids?
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Re: Crime Busters B
OK, I stand corrected... even so, I'm not entirely sure the gas released is always guaranteed to produce an audible fizzing sound like HCl + carbonate does? Even elephant toothpaste isn't that loud although it's a lot more pretty to watch XDUnome wrote:I found something on the H2O2/KI reaction here.pikachu4919 wrote:I'm not sure how you got that to happen bc if you try to write a balanced equation for it, you won't get a product that will be in gaseous form.Tailsfan101 wrote: One way to tell them apart is to put some iodine in it. If it fizzes, it's hydrogen peroxide. If not, water.
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Does anyone know any easy ways to tell the difference between LDPE and HDPE? Those are the only plastics I've really been struggling with.
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Re: Crime Busters B
Your best bet is density, and that's at the mercy of your event supervisor to hopefully make something that's around 0.93-0.94 g/cm^3 since that's in the middle of the densities of HDPE and LDPE.Tailsfan101 wrote:Does anyone know any easy ways to tell the difference between LDPE and HDPE? Those are the only plastics I've really been struggling with.
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Re: Crime Busters B
Thanks!pikachu4919 wrote:Your best bet is density, and that's at the mercy of your event supervisor to hopefully make something that's around 0.93-0.94 g/cm^3 since that's in the middle of the densities of HDPE and LDPE.Tailsfan101 wrote:Does anyone know any easy ways to tell the difference between LDPE and HDPE? Those are the only plastics I've really been struggling with.
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Re: Crime Busters B
You have to also make sure that both of the substances are new and are not old. If they are old, they might not work
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